Computational Investigation of Cathode Materials for Rechargeable Aqueous Zinc-Ion Batteries

The high safety, low manufacturing costs, and established component supply chain of rechargeable aqueous zinc-ion batteries (RAZIBs) position this new battery chemistry as an encouraging technology for utilization in grid-scale energy storage. Currently studied cathode materials for RAZIBs report promising initial battery capacity (>250 mA h g-1) and operating potential (ca. 1.5 V vs Zn/Zn2+); however, the battery cells suffer from severe capacity loss when cycling at practical rates (C-rate < C/2), hampering the commercialization of RAZIBs. Therefore, the development of RAZIBs as a technologically viable battery chemistry relies on (i) the identification of the capacity loss mechanism in currently leading cathode materials, and (ii) the discovery of novel cathode materials with high stability and battery operating metrics.

In this presentation, I will first discuss the investigation of the dissolution mechanism of MnO2 cathode materials from first-principles calculations of the Mn vacancy formation under battery operating conditions, and present potential capacity fade mitigating strategies identified from the obtained results. Then, a study on the feasibility of the utilization of binary oxides as cathodes for RAZIBs through an investigation of electrochemical stability and Zn2+ intercalation potential will be presented, which allowed for the proposal of promising alloying/doping elements for RAZIB cathodes. Finally, the high-throughput atomistic screening of more than 2000 previously synthesized materials for the discovery of next-generation RAZIB cathodes will be detailed, from which 3 electrochemically stable and previously unexplored cathode materials were identified.

Overall, this presentation will provide a unique insight into the operation mechanisms of cathode materials during RAZIB operation and offer a clear direction for the advancement of this battery technology, in direct support of the current commercialization efforts.